Looper-actuating mechanism for sewing machines



Jan. 5', 19 26. 1,568,391

A. B. CLAYTON LOOPER ACTUATING MECHANISM FOR SEWING MACHINES Filed Feb. 21 1922 2 Sheets-Sheet 1 INVENTOR I W TN 5 And/e105: 6701/01? A'ITORNEY ,Jm. 5', 1926. 1,568,397 I A. B. CLAYTON LObPBR ACTUA'I'ING IECHANISH FOR SEWING IACHINBS Filed Feb. 21. 1922 2 Sheets-Sheet 2 INVENTOR ZZZ/#M ATTORNEY Patented Jan. 5, 1926.

at-gene? UNITED STATES PATENT QEFICE ANDREW B. CLAYTON, F UNION, NEW JERSEY, ASSIGNOIR. TO THE SINGER MANU- FACTURING COMPANY, OF ELIZABETH, NEW JERSEY, A CORPORATION OF NEW' JERSEY.

LOOPER-ACTTJ'ATING MECHANISM FOR SEWING MACHINES.

Application filed February 21, 1922.

To all whom it may] concern Be it known that I, ANDRE-W B. CLAYTON,

a citizen of the United States, residing at Union, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Looper-Actuating Mechanisms for Sewing Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to improvements in looper mechanisms for sewing machines and particularly for chain-stitch sewing machines in which endwise and sidewise movements are imparted to a looper for cooperation with a reciprocating needle in the formation of chain-stitches.

The invention has for its object to im "prove the actuating mechanism for the loopers of chain-stitch sewing machines, whereby the operative path of movement of the loopers in completely assembled machines may be readily adjusted with respect to the needles to meet the various conditions of operations arising in commercial use of these machines.

To attain the object of the invention, the looper-carrier is adjustably secured upon a reciprocatory-oscillatory support operatively connected with independent actuating elements. The actuating element for imparting endwise movements to the'looper comprises an eccentric, adjustably secured upon a rotary shaft and embraced by a split-strap clamped upon the eccentric by means of a screw-bolt affording a fulcrum-pin for piv-v otally sustaining a pitman reciprocated by the eccentric and operatively connected with the looper-carrier. The sidewise movements of the looper are permitted by this pivotal support of the pitman and are derived from an inclined crank, carried by the actuating shaft and embraced by the sleeved portion.

of a gyratory arm having a universal joint connection with a sleeve mounted upon the looper-carrier support to reciprocate the lat- 'ter endwise but capable ofoscillatory move ments thereupon. I mits adjustment of the relative timing of the This construction per-,

Serial No. 538,208.

eccentric and .inclined crankwliereby the path of movement of the looper may be readily altered. Further, the operative con nections permit adjustment of the position of the looper which, together with the timing adjustments, readily enable an operator to accurately obtain the path of movement of the looper necessary to meet the particular operating condition.

In the accompanying drawings, Fig. 1 is a front view in elevation of a portion of the sewing machine embodying the present improved looper-actuating mechanism. Fig. 2 is a top plan view of the looper-actuating mechanism. F ig. 3 is a view substantially on the line of Fig. 1. Fig. 4 is a view substantially on the line g g of Fig. 2. Fig. 5 is a detail view of the inclined crank for imparting sidewise movements to the looper, together with the gyratory arm actuated thereby. Fig. 6 is a detail sectional view of the adjustable eccentric for imparting endwise movements to the looper, and Fig. 7 is a detail view of the looper-carrier support. 7

Referring to the drawings, the sewing machine, of which only a portion is shown, comprises a base 1 and an overhanging arm terminating in. a head 2. Journaled for reciprocatory movements in the head 2 is the needle-bar 3 to which is suitably secured the needle-clamp bracket 4 carrying one or more needles, as 5. Also ournaled for reciprocatory movements in the head 2 18 the presserbar 6 carrying the resser-foot 7 opposed to the feed-dog 8 operatingthrough suitable feed-slots, as 9, provided in the throatplate 10 and actuated in any wellknown manner to carry the work past the needles.

Journaled in. suitable bearings provided in lugs. as 11, on the base 1 is the rotary actuating shaft 12. .Adjustably secured upon the shaft 12 by means of setscrews, as 13, is an eccentric 14, embraced by a split-strap 15 having apertured ears, as 15, projecting therefrom. Straddling the strap 15 is a yoke 16 of a pitman l7 and threaded into the lower arm of the yoke 16 and secured therelit) upon by means of a nut 18 is a screw-bolt 19 of which the headed end rests upon the up per arm of the yoke and which bolt passes through said apertured ears By manipulation of the nut 18, the split-strap 15 may be caused to closely embrace the eccentric 14, and consequently wear between the eccentric and its embracing strap may be readily taken up. The screw-bolt 19, by means of the described construction, serves as a fulcrum-pin affording a pivotal support for the pitman 17 upon the strap 15, whereby lateral movement of the pitman is permitted.

The opposite end of the pitman 17 has a balLand-socket connection with a bolt 20 adjustably secured by means of a nut 21 in an elongated slot 22 provided in an arm 23 projecting laterally from a reciprocatory-oscillatory looper-carrier support 24. The looper-carrier support 24 is in the form of a tubular sleeve sustained for sliding and oscillatory movements upon a rod 25 suitably secured in apertures provided in the lugs 11 on the machine base. Secured upon the looper-carrier support 24 by screws, as 26, is a clamp 27 having a bracket-portion 28 in which is provided a grooved seat 29. Secured upon the seat 29, by means of a. screw 30, is the shank of a looper-carrier 31 upon which are suitably fixed the loopers 32 adapted to cooperate in the usual manner with the needles 5 in the formation of chainstitches. It will be apparent that, by reason of the described connections, rotation of the eccentric 14 will impart reciprocating movements to the pitman 17, which in turn imparts oscillatory movements to the loopercarrier support to transmit to the loopers their endwise movements.

In order to permit lubrication of the outer surface of the actuating eccentric 14 the flanged end 33 thereof, into which the securing set-screws 13 are threaded, is provided with a radial aperture 34 normally held closed by a ball 35 acted. upon by a spring 36. The aperture 34 communicates with a plurality of reservoirs 37 provided w'thin the eccentric and from which reservoirs the lubricant is conducted to the outer surface of the eccentric, by means of passages. as 38. Lubricating means is also pro vided for the bearing surface of the fulcrum-pin 19 which is formed with an aper' true 39 extending longitudinally thereof permitting insertion of the lubricant, which is conducted to the outer surface of the fulcrum-pin through a plurality of transverse passages, as 40.

Sidewise movements are imparted to the looper by means of an inclined crank 41 adjnstably secured upon the rotary-shaft 12 by means of the set-screws 42, which are threaded into a circumferentially disposed rib 43. intermediate the ends of the crank. Embracing the crank 41'upon opposite sides of the rib 43 is the sleeved portion of a gymtory arm 44. Said sleeved portion comprises spaced members 45 having semi-spherical surfaces 46 complementary to similar surfaces 47 provided on caps, as 48, individually secured in position upon the members 45 by means of screws, as 49. As will be apparent, the rib 43 serves to prevent movement of the gyratory arm in the direction of the axis of the crank, while the arm itself may be readily detached from the crank by removal of the caps 48. At its lower end the arm 44 has ball-and-socket connections with a lateral arm 50 projecting from a sleeve 51. The sleeve 51 is journaled for oscillatory movements upon the looper-carrier support 24, being held against endwise movements thereupon by the hub of the .arm 23 and by a split cap '52 threaded upon the end of the support 24 and held in position by means of a collar 53 clamped upon the cap 52.

Upon rotation of the inclined crank 41 gyratory movements are imparted to the arm 44 one component of which is taken up by the idle oscillation of the sleeve 51 upon the looper-carrier support. The other component of movement of the arm 44 imparts to the support 24 endwise movements upon the rod 25, whereby sidewise movements are transmitted to the looper or loopers. By circular adjustment of the eccentric 14 or of the inclined crank 41 upon the shaft 12, i. e., changing their timing with respect to each other the path of movement of the loopers may be appreciably altered to meet different requirements. It will be observed from the dotted lines in Fig. 2 that the center line of movement of the loopers in the position of the parts as shown is inclined to the direction of feed. The adjustments provided in the operative connections permit of correctly setting and operating the loopers without requiring the extreme accuracy in manufacture essential in prior constructions.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, the combination with a. main-shaft, a reciprocatory needle, and a looper, of a rotary eccentric and a rotary inclined crank deriving their operative movements from said main-shaft for actuating said looper for cooperation with said needle in the formation of stitches, operating connections between the looper and said eccentric for imparting endwise stitchformi-ng movements to said looper. and operative connections between the inclined crank and the looper for imparting sidewisc movements thereto.

2. In a sewing machine. the combination with a main-shaft, a reciprocating needle. and an endwise and si'dewise movable looper adapted to cooperate with said needle in the formation of stitches, of actuating elements for said looper comprising a rotary eccentric and a rotary inclined crank deriving their operative movements from said main-shaft, operative connections between the looper and said eccentric and inclined crank for imparting the endwise and sidewise stitch-forming movements to the looper, and means permitting adjustment of the relative timing of said eccentric and crank.

3. In a sewing machine, the combination with a reciprocating needle, and an endwise and sidewise movable looper adapted to cooperate with said needle in the formation of stitches, and a rotary actuating shaft, of actuating elements for said looper comprising a rotary eccentric and a rotary inclined crank carried by said shaft, means permitting adjustment of said crank upon said shaft to vary the timing thereof with respect to said eccentric, and operative connections between the looper and said eccentric andinclined crank for imparting the endwise and sidewise movements to the looper.

4. In a sewing machine, in combination, a main-shaft, a reciprocating needle, a looper cooperating with said needle in the formation of stitches, a looper-carrier, a rotary eccentric deriving its operative movements from said main-shaft, operative connections between said eccentric and the looper-can rier for imparting endwise movements to the looper, a rotary inclined crank deriving its operative movements from said mainshaft, and a universal-joint connection between said crank and the looper-carrier for im parting sidewise movements to the looper.

5. In a sewing machine, in combination, a reciprocatory needle, an endwise and sidewise movable looper cooperating with said needle in the formation of stitches, a loopercarrier, means for imparting the sidewise movements to said looper, and means for imparting the endwise movements to the looper including a rotary actuating shaft, an eccentric carried by said shaft, a strap embracing said eccentric, a pitman pivotally connected with said strap to permit of lateral swinging movements of said pitman relatively to said strap, and an operative connection between the pitman and said looper-carrier.

6. In a sewing machine. in combination, a main-shaft, a reciprocating needle, a

looper cooperating with said needle in the formation of stitches, a looper-carrier, a rotary eccentric deriving its operative movements from said main-shaft, a strap embracing said eccentric, a pitman connecting said strap and the looper-carrier for imparting endwise stitch forniing movements to the looper, a pivotal support for said pitman permitting lateral movement thereof. a rotary inclined crank deriving its operative'movements from said mainshaft, and

a universal-joint connection between said inclined crank and the looper-carrier for strap embracing said eccentric, and a pitman pivotally supported by said strap operatively connected with said support, and means for imparting reciprocatory movements to said support comprising a rotary inclined crank deriving operative movements from said main-shaft, a sleeve mounted for oscillatory movements upon said support, and a universal-joint connection between said crank and said sleeve.

In a sewing machine, in combination, a reciprocating needle, a looper cooperating with said needle in the formation of stitches, a looper-carrier, a. reciprocatory-oscillatory support sustaining said looper-carrier, a rotary shaft, an eccentric adjustably secured upon said shaft, a strap embracing said eccentric, a pitman pivotally supported by said strap and operatively connected with said support for imparting oscillatory movements to the latter, an inclined crank carried by said shaft, a sleeve mounted for 0scillatory movements upon said support, and a univer al-joint connection between said crank and said sleeve.

9. In a sewing machine, in combination, a

reciprocating needle, an endwise and sidewise movable looper adapted to cooperate with said needle in the formation of stitches, a looper-carrier, a rotary shaft, an eccentric carried by said shaft, a strap embracing said eccentric, a pitman having a yoke straddling said strap, a fulcrum-pin pivotally securing said yoke upon said strap, an operative connection between said pitman and said looper-carrier for imparting one of said movements to said looper, and means for imparting the other of said movements to said looper. c

, 10. In a sewing machine, the combination with a reciprocating needle, and a looper co operating with said needle in the formation of stitches, of means for actuating said looper including a rotary shaft, an eccentric carried by said shaft. a split strap embracing said eccentric, a fulcrum-pin affording means for clamping the strap upon said eccentric, a pitman pivotally sustained upon said strap by said fulrum-pin, and operative connections between said pitman and the looper for imparting movements thereto.

11. In a sewing machine, the combination with a reciprocating needle, and a looper cosite sides of its oireuniferentially disposed rib, and operative connections between said arm and the looper for imparting move- 10 ments 'to the latter,

In testimony whereof, I have signed my name to this specification.

ANDREW B. CLAYTON. 

